The present disclosure relates to an image reading device, an image forming apparatus, and an image reading method.
In general, there has been known an image reading device that includes an ADF (Automatic Document Feeder) and two image sensors. The ADF conveys a document sheet along a predetermined document sheet conveyance path. In addition, in a double-side mode in which images are read from both sides of the document sheet, the two image sensors respectively read the images from both sides of the document sheet that is moving in the document sheet conveyance path, and output image signals that respectively correspond to the read images.
In addition, the image signals that are analog, are converted to digital image data by signal conversion circuits such as AFEs (Analog Front Ends). Furthermore, an image processing portion performs various types of image processing to the digital image data.
Furthermore, the image reading device includes two CISs (Contact Image Sensors) for reading the images from both sides of the document sheet. In that case, the signal conversion circuit is provided for each of the CISs.